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    <title>Document</title>
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    <div></div>
    <script>
        var date=new Date();
        var div= document.querySelector('div');
        function pluszero(x){
                if (x<10){
                    x='0'+x;
                }
                return x;
            }
        function countdown(datex){
            var date1= new Date(datex);
            var time= date1-date;
            var d=Math.floor(time/1000/60/60/24);
            var h=Math.floor(time/1000/60/60%24);
            var m=Math.floor(time/1000/60%60);
            var s=Math.floor(time/1000%60);
            div.innerHTML=pluszero(d)+'-'+pluszero(h)+'-'+pluszero(m)+'-'+pluszero(s);
        }
        countdown('2020-02-29 00:00:00');
        
    </script>
</body>
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